The present invention is generally related to medical devices and apparatus. In particular, the invention provides systems, methods, devices, and kits for treating a patient""s ear. In one embodiment, the invention provides a system and method for myringotomy with or without tympanostomy tube placement.
Otitis media is among the most common diagnosis made by pediatricians. A majority of children may have at least one episode of otitis media (xe2x80x9cearachexe2x80x9d) prior to their third birthday. Otitis media is often caused by an inability of the eustachian tube to drain fluid from the middle ear. Otitis media is often treated with antibiotics.
A significant number of children exhibit recurrent episodes of otitis media and/or otitis media with effusion. Treatment of these more severe cases often involves the placement of a tympanostomy tube through the tympanic membrane so as to provide adequate drainage of the middle ear and reduce the likelihood of future infections. Tympanostomy tubes provide fluid communication between the middle and outer ear, and typically fall out spontaneously within about a year of placement. Tympanostomy tube placement is among the most common surgical procedures performed in the pediatric population. It has been estimated that more than a million tympanostomy tubes may be placed each year, with typical patients being between about 18 months and 3 years of age at the time of the procedure.
Tympanostomy tube placement is typically performed in an out-patient surgery setting under general anesthesia. The external auditory canal and tympanic membrane are examined under microscopic visualization through a hand-held conical shaped speculum. An incision or myringotomy is made in the tympanic membrane, typically using an elongate, small profile scalpel which the physician extends through the conical speculum. Fluid may be aspirated through the myringotomy, and a tympanostomy tube is placed so as to extend through the tympanic membrane.
A wide variety of tympanostomy tubes are commercially available, and a still wider variety of others tubes have been proposed. A number of systems have been proposed to both perform the myringotomy and deploy the tympanostomy tube with a single treatment assembly. In recent years, more complex and expensive systems have been proposed for diagnosis or treatment of the tissues of the ear, including systems using laser energy for forming a myringotomy, video systems for imaging of the ear canal, and the like. These various alternatives have, not surprisingly, been met with varying degrees of acceptance.
A standard tympanostomy tube placement procedure is both effective and quite safe. Nonetheless, further improvements would be desirable. In particular, there are both risks and costs associated with out-patient surgical procedures performed under general anesthesia. For example, a significant portion of the risk and cost of tympanostomy tube placement is associated with the administration of general anesthesia, i.e., the need for an operating room, the presence of an anesthesiologist, and related recovery room time.
In light of the above, it would be desirable to provide improved devices, systems, methods, and kits for treatment of the tissue structures within the auditory canal. It would generally be beneficial if these improvements facilitated myringotomy with or without tympanostomy tube placement without having to resort to general anesthesia, thereby allowing these common procedures to be performed in a doctor""s office (rather than in an outpatient surgical facility). It would be further beneficial to maintain or enhance the physician""s control over the procedure by, for example, allowing verification of intended and actual tympanostomy tube placement location, enhanced viewing and control, and improved safety. It would further be desirable if these improvements could be provided while decreasing the overall procedure time, and ideally, at a reduced overall procedure cost.
The present invention provides improved devices, systems, methods, and kits for treating the tissue structures of the ear. The invention often makes use of a guide structure that can mechanically register a treatment probe with a target region of the tympanic membrane or eardrum. Mechanical registration may be provided by a structure which is fittingly received in an external auditory canal of the ear. The guide structure will often include a conformable body (typically comprising a compressible foam, or the like) so as to allow the guide structure to accommodate a range of differing auditory canal anatomy. The guide structure may further include an articulating mechanism for selectively orienting the treatment probe toward the target region of the tympanic membrane. The articulating mechanism will often selectively orient a probe lumen, with the treatment probe having a shaft fittingly sliding in the probe lumen so that engagement between a positioning surface of the guide structure and a tissue surface of the patient""s ear maintains registration of the treatment probe. The guide structure may also support a videoscopic image capture device, illumination transmitting optical fibers, an aiming beam transmitter, and the like. Advantageously, such structures facilitate performing treatment procedures such as myringotomy, tympanostomy tube placement, and the like, under local (rather than general) anesthesia, often in a doctor""s office (rather than an out-patient surgical facility).
In a first aspect, the invention provides a method for treating an ear of a patient. The ear has a tympanic membrane. The method comprise mechanically registering a guide structure with a target region of the tympanic membrane. The target region is treated by actuating a treatment probe while the treatment probe is oriented by the registered guide structure.
Orientational alignment between the guide structure and the tympanic membrane may be maintained by engagement between a surface of the guide structure and an external auditory canal. This engagement may be sufficient to maintain orientation of the treatment probe without manual support of the guide structure or treatment probe. The use of a conformable body of the guide structure can facilitate the orientation maintaining engagement. The conformable body may comprise a compressible foam, a solid elastomer, a balloon, or the like, and may optionally expand radially within the auditory canal. An agent (such as a local anesthesia agent, an antiseptic agent, an antibiotic agent, or the like) may be dispensed from the guide structure, the agent optionally being dispensed from the compressible foam. In alternative embodiments, one or more such agents may be dispensed before insertion of the guide structure and/or after its removal. In some embodiments, registration of the probe and target region may be provided at least in part by engagement (preferable in the form of gentle pressure) between the guide structure and the skull (often the side of the skull) of the patient.
The guide structure may be registered by articulating a treatment lumen of the guide structure relative to a positioning surface of the guide structure. For example, the guide structure may comprise a shaft eccentrically carrying the treatment lumen. The shaft may rotate within the auditory canal about an axis with the treatment probe precessing about the axis so as to orient the probe toward the target region. The positioning surface of the guide structure may be disposed over the shaft with a bearing therebetween to facilitate rotation without injury to the tissue surface engaged by the positioning surface. The shaft may flex during rotation so as to accommodate a bend of the auditory canal. The probe and/or other components of the treatment system within the guide structure may likewise flex during rotation.
Registration of the guide structure may be videoscopically directed, the guide structure optionally supporting a video image capture device. The tympanic membrane may be illuminated by the guide structure, typically using an illumination source and/or optics (such as a fiber optic bundle, glass rod, or other optical waveguide). The registration of the probe with the target region may optionally be verified by displaying a marker indicating which portion of the tympanic membrane is aligned with the probe. For example, an aiming beam may be transmitted onto the tympanic membrane from the guide structure to generate the marker or pointer. The aiming beam may comprise, for example, laser light energy having a frequency within the visible range. In some embodiments, a reticule or image template may be superimposed on the image displayed to the system operator to aid registration.
A system operator disposed in front of the patient may view an image of the tympanic membrane while a head of the patient is upright. The system operator may manipulate a handle coupled to the shaft of the guide structure to register the guide structure and actuate the treatment probe. In the exemplary embodiment, the guide structure handle is a large profile body, similar in appearance to an earmuff when in use. The system of the present invention is particularly well-suited for tympanostomy tube placement without general anesthesia.
The treatment probe will typically pierce the tympanic membrane. A tympanostomy tube may be advanced through the pierced membrane, often while supporting the tympanostomy tube with the guide structure. The treatment probe may carry the tympanostomy tube. Alternatively, separate probes may be used to pierce the membrane and deploy the tympanostomy tube. In still further alternatives, the membrane may be pierced using laser energy or the like. Fluid may be drained from distally of the pierced membrane by the treatment probe, by a separate aspiration structure supported by the guide structure, or the like. Fluid drainage may be effected by an aspiration lumen, by an absorbent structure such as a blotting or wicking element, or the like.
In another aspect, the invention provides a system for treating an ear of a patient. The ear has a tympanic membrane and a tissue surface. The system comprises a guide structure having a proximal orientation and a distal orientation. The guide structure has a positioning surface. A tympanic membrane treatment probe is oriented by the guide structure. The guide structure maintains registration of the treatment probe with a target region of the tympanic membrane when the positioning surface engages the tissue surface of the ear.
The tissue surface typically comprises an auditory canal. The guide structure will often include a conformable body insertable into the auditory canal. A shaft may be rotatably disposed within the conformable body so as to rotate about an axis. The treatment probe can be oriented eccentrically relative to the axis so that rotation of the shaft selectively registers the treatment probe with the target region. The shaft may be laterally flexible to conform with a bend of the auditory canal during rotation of the shaft. Similarly, the treatment probe may also be flexible.
The conformable body may comprise a compressible material such as a foam. In some embodiments, an agent such as a local anesthetic agent, an antiseptic and/or antibacterial agent, an antibiotic agent, and/or the like may be disposed on or in the foam, or the agent may otherwise be dispensed from the guide structure. The guide structure may further include one or more aspiration and/or irrigation lumens, or such lumens may alternatively be incorporated into the treatment probe. Such aspiration and/or irrigation may be used to clear Cerumen (earwax) for imaging of the tympanic membrane, fluid accumulating distally of the tympanic membrane, and the like.
An image capture device may be supported by the guide structure for imaging the tympanic membrane. The image capture device may coupled to a monitor, the image capture device typically comprising a Charge-Coupled Device (CCD) and associated imaging optics (such as a coherent fiber optic bundle, one or more rod or standard lenses, and the like). At least a portion of the image capture device may be removably couplable to the guide structure, which may allow the use of disposable guide structures at a reasonable cost. An illumination source may also be carried on the guide structures for illuminating the tympanic membrane during imaging. The exemplary illumination source may comprise illumination optical fibers.
The system will preferably include aiming means for identifying an orientation of the treatment probe relative to the tympanic membrane. In many embodiments, a light beam (such as from a laser or light-emitting diode) may be directed onto the tympanic membrane at a location aligned with the treatment probe. Alternative embodiments may make use of a reticule superimposed on the image of the tympanic membrane as shown in a monitor to the system operator, a template superimposed on the image to indicate the target region, or the like. Such aiming structures can verify registration of the treatment probe with the target region before, during, and/or after piercing the tympanic membrane, tube deployment, and the like.
The treatment probe will often have a distal tip for piercing the tympanic membrane. Optionally, the distal tip may comprise a cutting edge or blade. A tympanostomy tube may be releasably carried on a shaft of the probe proximally of the tip. An exemplary tympanostomy tube comprises a proximal flange and a distal flange with a tubular body therebetween, the tubular body having an elongate opening with a first cross-sectional dimension and a second cross-sectional dimension greater than the first. The tip of the probe shaft may have a distal edge oriented along the height when the tympanostomy tube is carried on the shaft. The distal surface of the distal flange of the tympanostomy tube may angle proximally and radially outwardly to facilitate advancing the distal flange through the myringotomy.
A limit surface of the treatment probe may engage a limit surface of the guide structure or the tympanic membrane so as to inhibit axial movement of the shaft after the probe pierces the tympanic membrane. This can help avoid inadvertent injury to the middle and/or inner ear structures or undesired positioning of the tube distally of the tympanic membrane within the middle ear. In the exemplary embodiment, engagement of the limit surfaces inhibits movement when the distal end of the probe advances from the guide structure by a distance in a range from about 1.0 mm to about 40 mm.
The treatment probe may comprise a probe shaft disposed in a lumen of the guide structure. The probe shaft may be coupled to an actuator which is accessible when the positioned surface engages the tissue surface. The probe shaft may advance axially with the lumen in response to movement of the actuator. The lumen may be selectively repositionable relative to the positioning surface for selective registration of the treatment probe with the target region for example, the lumen may be supported by a shaft which rotates relative to the positioning surface, with the lumen being eccentrically oriented and/or eccentrically disposed relative to the axis of rotation of the shaft.